190 
In the symbolic notations hitherto used the force culty that the necessary raw materials are released 
NATURE 
component is always written first and the component | 
of motion producing it is written after it as a suffix, 
It is therefore important that the same convention 
should be followed in the proposed nomenclature, 
Thus “ Lopi”’ will stand for the X, of my “ Stability in 
Aviation,” while ‘‘ Pilo”’ stands for N,. These words 
take no longer to write than logx or sinx, and it 
| 
| 
would be easy to employ them in writing down | 
formulz, which would thereby gain much in clearness 
and suggestiveness. G, H. Bryan. 
Plastic Flowing of Metals. 
from time to time on the plastic flowing of metals 
under stress, might not these results have a bearing 
on the action of the fusion of wires by electric cur- 
rents? For instance, it is well known to electrical 
engineers that erratic results are obtained by the use 
of the present formule for calculating the so-called 
“ fusing" currents. of wires. } 
At present, so far as the theory of electrical fuse 
wires is concerned, these theories deal merely with the 
generation of heat per unit length in the wire, and 
the loss of heat per unit length of the wire. Now, 
whatever the gain or loss of heat may be, that in itself 
is surely merely a cause increasing the plasticity of the 
wire, and thereby allowing the mechanical stresses 
acting on the wire to break it. Consequently, it would 
appear that any theory which omits all reference to 
the mechanical stresses set up by the heating is neces- 
sarily incomplete, and represents only a portion of the 
process. ; 
At present, owing to lack of experimental data, it 
is impossible to say whether one can predict the fusing 
for any metal of given dimensions, but so far the 
results obtained seem more promising than by the older 
methods. W. H. F. Murpocu. 
Westerlea, Mill Hill, Middlesex, November 1. 
Optical Deterioration of the Atmosphere and Volcanic 
Eruptions. 
In Nature of October 5 it is stated that the cause of 
the optical deterioration of the atmosphere in July and 
August “is for the time being still in doubt. Up to 
the present no reports of volcanic eruptions have come 
to hand from any part of the globe.” 
I wish to state that in July a strong outburst 
occurred of the Stromboli volcano, and that on July 4 
there was an extraordinary eruption of fluid and in- 
candescent lava to a great height, followed by a thick 
rain of lapilli and ashes. The emission of enormous 
columns of black cloud lasted many days. 
: A. Ricco. 
R, Osservatorio di Catania ed Etneo, 
October 30. 
POSITION AND PROMISE OF BRITISH 
DYESTUFF MANUFACTURE. 
13 ia question is frequently asked: ‘What is 
being done to produce British dyes?” 
Broadly, it may be said, the problem is being 
dealt with as efficiently as could be expected under 
present conditions. The difficulties may be 
roughly classified as follows :— 
(1) The raw materials necessary for dyestuff 
manufacture ate also in the main the raw materials 
from which high explosives are made, as well as 
other important products of the utmost value 
in the present war. It is only with great diffi- 
NO. 2454, VOL. 98] 
| means of saving thousands of our men and 
REGARDING the interesting research work published | 
[NOVEMBER 9, 1916 
by the Munitions and other Government Depart- 
ments. 
(2) There is an extraordinary shortage of ade- 
quately trained chemists. This shortage has been 
accentuated owing to the great demand for 
chemists in explosives works, the sending of 
chemists to the Front to study questions of gas 
poisons, etc., the recruiting for military service, 
and the failure of tribunals to appreciate that one 
clever chemist working at home may discover the 
accounting for the destruction of thousands of 
the enemy. 
(3) The problems to be solved by chemists are 
not only numerous, but many are exceedingly in- 
tricate and complex. The patents taken out by 
Germans in this country for many years past have 
been drawn up in an _ extraordinarily skilful 
manner by the help of our ablest lawyers, patent 
agents, and experts, so as to disguise in every 
conceivable way the method of arriving at the 
production of the patented article or its manu- 
facture. This has been a scandal that has been 
allowed to gain force year by year. It is almost 
incredible that we should have allowed ourselves 
to be hoodwinked in this way, granting these great 
privileges to powerful German firms in order to 
restrain manufacture in this country. : 
(4) A serious difficulty will have to be faced in 
settling the question as to how to distribute 
amongst chemical manufacturers the many 
problems that await solution. It is most desirable 
to avoid overlapping of effort in research, ete., 
or quite unnecessary duplication of plant. Other- 
wise we shall have, say, one firm trying to 
solve too many problems and others, quite 
competent and suitable, making no efforts at 
all. These questions, it is proposed, shall be 
dealt with by some central authority, such as the 
recently formed Association of British Chemical 
Manufacturers, one of whose objects is to help 
manufacturers in this and many other desirable 
ways, e.g. to unite their efforts to fight the 
common foe rather than to compete with one an- 
other at home. Had such an association been in 
existence early in the war, these particular 
troubles would have been largely avoided, and 
much valuable time and money saved. 
(5s) The U.S.A. Government, although relatively 
a Free Trade one, has lately promised duties of 
more than 100 per cent. on dyestuffs and chemical 
products after the war so as to help America 
to build up what to all intents and purposes is 
for them, as it is for us, an infant industry. 
Our Government has so far resolutely refused 
any definite indication in that direction; and yet, 
without heavy protective duties, the chemical in- 
dustry of the finer products, including dyestuffs, 
ecannot possibly. be built up and firmly established 
in this country. 
(6) It is now quite clearly recognised that only 
very large undertakings can afford to carry on the 
kind of research that is essential for the success of 
the dyestuffs industry, This is perhaps the chief, 
